Control system for a jet propulsion boat

ABSTRACT

A control system for jet-powered boats includes a water jet propulsion group; an ejection nozzle of the water jet oriented to direct the water jet at least in a longitudinal direction; a jet deflector changing flow direction of at least part of the water relative to the longitudinal axis of the boat, the deflector being controllable to progressively adjust the part of the diverted water jet and set a neutral thrust condition, in which the boat is stationary, thrusting forward with variable speed and thrusting backward with a predetermined or variable speed; a control member of the deflector position; a setting member of the deflector that adjusts the deflector to achieve a neutral thrust condition, the deflector being adapted for a predetermined and pre-set neutral thrust position; and a control member of the deflector in the preset position of neutral thrust, canceling any subsequent customization settings.

FIELD OF THE INVENTION

The present invention relates to a control system for jet propulsion boats comprising:

at least one water jet propulsion unit, such as a turbine or the like;

a water jet ejection nozzle connected to the outlet of said water jet propulsion unit, which nozzle is oriented in such a way as to direct the water jet essentially at least in the longitudinal direction of the boat;

a jet deflector to change the flow direction of at least part of the water jet leaving the nozzle with respect to the direction essentially parallel to the longitudinal axis of the boat and along a direction from the bow to the stern of the boat;

said deflector being controllable in such a way as to progressively vary said part of the water jet deviated from said direction essentially parallel to the longitudinal axis of the boat and along a direction from the bow to the stern of the boat, to determine a neutral thrust condition in which the boat is stationary, thrust forward with variable speed and thrust backward with at least a predetermined speed or with variable speed;

a control member for the position of the deflector to alternatively bring one of said conditions;

a member for setting said deflector so as to adjust the deflector to obtain the neutral thrust condition, said deflector being provided with a predetermined and preset neutral thrust position.

BACKGROUND OF THE INVENTION

Similar systems are known, for example, from documents US2001029134, US2008233811, U.S. Pat. No. 9,682,757B1, US2002028615A1 or US2004144293A1.

In these known systems there is a control element providing the variation of the position of the water flow deflector to adjust the position of the deflector in which the boat is in neutral running, i.e. under no pressure forward or reverse, but the action of the deflector on the flow of water leaving the turbine is such as to guarantee a condition of balance between forward thrust and backward thrust of the boat itself.

The different customizations however mean that an initial reference position that is always identical and from which to start for any custom trim adjustments due to the contingent condition and specific characteristics of the boat's hull is lost.

This is therefore a need that is not met and which the present invention aims at fulfilling.

SUMMARY OF THE INVENTION

The object of the present invention is therefore to provide a control system of jet propulsion boats in which it is possible to return at any time and with ease and speed to a condition of the boat and the engine that defines a stable reference over time and always the same.

According to a first aspect of the present invention, this object is achieved with a control system of jet propulsion boats, comprising:

at least one water jet propulsion unit, such as a turbine or the like;

a water jet ejection nozzle connected to the outlet of said water jet propulsion unit, which nozzle is oriented in such a way as to direct the water jet essentially at least in the longitudinal direction of the boat;

a jet deflector to change the flow direction of at least part of the jet of water leaving the nozzle with respect to the direction essentially parallel to the longitudinal axis of the boat and along a direction from the bow to the stern of the boat;

said deflector being controllable in such a way as to progressively vary the said part of the jet of water deviated from the said direction essentially parallel to the longitudinal axis of the boat and along a direction from the bow to the stern of the boat, to determine a neutral thrust condition in which the boat is stationary, thrust forward with variable speed and thrust backward with at least a predetermined speed or with variable speed;

a control member for the position of the deflector to alternatively bring one of said conditions;

a member for setting the said deflector so as to adjust the deflector to obtain the neutral thrust condition, the said deflector being provided with a predetermined and preset neutral thrust position

characterized in that

said system comprises a control member of said deflector in the preset neutral thrust position, canceling any subsequent customization settings.

A system of the aforementioned type can be made according to different variants which may include manual members for moving the deflector and manual parts for setting the boat's trim by setting a customized deflector position.

Alternatively, the system can be electromechanical, electro-hydraulic or electro-pneumatic by providing a deflector positioning actuator which is hydraulic, mechanical or pneumatic and by providing at least one electric motor, a hydraulic or pneumatic pump in combination with servo-controlled valves which motors and which servo-controlled valves are activated and deactivated by a control signal generated by a control unit as a function of a command signal generated by a control unit.

In an embodiment, the system provides that the control member of the variable position of the deflector to control the forward, reverse and neutral motion conditions are separated from the trim control members controlling the position of the deflector to determine a position corresponding to the neutral condition and adapted to the fluid dynamic behavior of the boat. This can be caused either by the specific fluid dynamic characteristics of the boat's hull, but also by specific environmental conditions, such as currents, winds, load distribution and other changes in operating conditions determined by external agents.

Therefore, independently of the control condition of the deflector position having the purpose of steering the boat, the trim control member allows to set a condition of balance between the forces acting on the boat such as to keep the same stationary or to have a balance between an overall push forward and an overall push back.

The control element for moving the deflector in a predetermined condition corresponding to a neutral condition, that is, a balance between the flows of the jet that generate a forward and a backward thrust of the boat allows to always return quickly and safely to a condition of positioning of the deflector which is fixed, stable and in which at the time of construction of the propeller, or of the turbine and of the nozzle with the deflector, the flows generated by the deflector are equivalent in relation to the thrust exerted on a load and this regardless of external influences or to the boat in which the engine is mounted.

This condition allows to always have the possibility of returning to a certain and stable condition in order to reconstruct the customized trim settings by means of the deflector control members and/or the trim control members.

Further improvements of the invention are subject of the dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features and advantages of the present invention will become clearer from the following description of an executive example schematically illustrated in the block diagram of FIG. 1.

FIG. 2 shows an execution variant of the example of FIG. 1.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

With reference to FIG. 1, the block diagram refers to a control system of jet propulsion boats according to the present invention.

Said system comprises in its more general form, at least one water jet propulsion unit, such as a turbine or the like;

a water jet ejection nozzle connected to the outlet of said water jet propulsion unit, which nozzle is oriented in such a way as to direct the water jet essentially at least in the longitudinal direction of the boat;

a jet deflector to change the flow direction of at least part of the jet of water leaving the nozzle with respect to the direction essentially parallel to the longitudinal axis of the boat and along a direction from the bow to the stern of the boat;

said deflector being controllable in such a way as to progressively adjust said part of the water jet deviated from the said direction essentially parallel to the longitudinal axis of the boat and along a direction from the bow to the stern of the boat, to determine a neutral thrust condition in which the boat is stationary, thrust forward with variable speed and thrust backward with at least a predetermined speed or with variable speed;

a control member for the position of the deflector to alternatively bring one of said conditions;

a member for setting said deflector so as to adjust the deflector to obtain the neutral thrust condition, said deflector being provided with a predetermined and preset neutral thrust position.

Systems of this type according to one or more executive variants are known and are described for example in the documents: US2001029134, US2008233811, US2008233811, U.S. Pat. No. 9,682,757B1, US2002028615A1 or US2004144293A1. The system according to the present invention is applied to any of the devices described in the aforementioned documents and the descriptions of these devices are to be considered part of the present description, in particular as regards the construction of the water jet thrusters, the nozzles and the deflectors, as well as the command and control systems for the position of the deflectors with reference to the forward, reverse, neutral shift and trim settings.

As also appears from the cited documents, the boat can be equipped with one or more engines, it can be a traditional boat, or even a so-called jet ski or other boats belonging to different types.

The embodiment in FIG. 1 shows a system in which it is provided a separate control element indicated with 100 and with 110 respectively for the forward, backward, and acceleration forward and/or rearward movement commands as indicated with 111, 112, 113.

There are also control elements for adjusting the boat's trim and with which it is possible to set a customized position of the deflector.

The trim control member comprises commands for moving the position of the deflector in a condition in which the deflector is brought into a condition to unbalance the flows forward and backward with respect to each other respectively with the controls 101, 102.

The trim control member 100 also has a command 103 to reset the position of the deflector modified with the buttons 101 and/or 102 and bring it to a predetermined default position of the same in which the forward and backward flows are balanced during a factory setting or installation of the engine on a boat.

Control elements 100 and 110 send the commands in the form of electrical signals to a control unit 120. The unit can be of any type, only hardware, in which the hardware is configured to perform the functions foreseen for the unit and which it will be described below, comprising a generic hardware that runs a software consisting of a program in which the instructions are configured to treat the signals received from the control elements 100 and 110 so as to perform the aforementioned functions.

Control unit 120 generates control signals as a function of the input signals provided by the control elements 110, 100 which are sent to the jet ejection nozzles indicated with 160 to adjust, for example, the flow rate of the jet and to a driver 130 generating in turn, the supply or activation and deactivation signal of a motor 140 acting on the deflector 150, for example in the form of a flow deflection or inversion tile thanks to which the flow leaving the nozzle is at least partially deflected in opposite directions to generate a condition of neutral position of the boat, that is in the stationary condition of the boat or in the forward or reverse shift.

As already indicated in the foregoing description and claimed below, it is possible to provide various embodiments with respect to the electromechanical system described herein.

In addition to the possible electro-pneumatic or electro-hydraulic options in which the motor does not directly operate a mechanical actuator, but a hydraulic or pneumatic pump that supplies pressure fluid to a corresponding actuator and which is generally provided in combination with reverse flow valve systems or its adjustment, solutions with manual operation are also possible in which the mechanical and/or hydraulic and/or pneumatic force is generated manually thanks to a mechanical member for applying the muscular force and/or a manual pump.

The different solutions are either used in parallel fields as in the directional control of boats or in fields such as the control of motor vehicles or the like.

The embodiment in FIG. 2 provides that the command interface of the steering and running conditions of the device is not separate from the command interface for the boat's trim conditions.

In this case, the control element indicated with 200 comprises acceleration commands 213, deflector movement commands so as to generate an imbalance of the flow in the forward direction of travel 201, commands for backward movement 202 and the reset command of the initial position of the deflector 203.

The remaining configuration follows what was previously described with a control unit 220, nozzle 260, driver of engine 230, engine 240 and deflector 250.

It is clear that in this configuration, the function of controls 201 and 202 can be modified by steering commands to control the boat forward and backward and trim commands to change the boat's trim thanks to a selector (not shown) transferring the control signals to a hardware software unit of control unit 220 which therefore operates alternately for steering the boat or for adjusting the trim. 

The invention claimed is:
 1. A nozzle comprising: a body defining a longitudinal axis, the body having a base at a proximal end and one or more lateral walls; a longitudinal bore defined within the body, the longitudinal bore having an open first end at the base of the body and a dead second end; a recess defined within the one or more lateral walls, the recess having a bottom and side walls extending perpendicularly to the longitudinal axis of the body; and a lateral bore defined within the body, the lateral bore fluidly connecting the longitudinal bore to an opening in the recess, the lateral bore having a diameter smaller than a diameter of the longitudinal bore, wherein the opening is positioned at an apical end of a triangular slit within the bottom of the recess, the triangular slit being perpendicular to the longitudinal axis of the body, the triangular slit further having a base end disposed between the side walls of the recess.
 2. The nozzle of claim 1, wherein the longitudinal bore has a proximal portion extending from the open first end and a distal portion joined to the lateral bore, the proximal portion having a larger diameter than the distal portion, a frusto-conical portion connecting the proximal portion to the distal portion.
 3. The nozzle of claim 2, further comprising a side bore coaxial with the lateral bore, the side bore extending from the distal portion of the longitudinal bore to an aperture in one of the one or more lateral walls of the body opposite to the recess.
 4. The nozzle of claim 3, wherein the side bore is threaded.
 5. The nozzle of claim 3, wherein the side bore is configured to receive a plug closing the side bore.
 6. The nozzle of claim 1, wherein the bottom of the recess is convex and has a plurality of faces, the triangular slit being defined in a central position within the bottom.
 7. The nozzle of claim 1, wherein the body has a multilateral distal portion defined by a plurality of sides and a proximal portion adapted to engage an opening in a nozzle bar.
 8. The nozzle of claim 7, wherein the plurality of sides extends from the proximal portion to a distal end of the body.
 9. The nozzle of claim 7, wherein the proximal portion is configured to provide a threaded, flanged, quick-connect, or bayonet connection.
 10. The nozzle of claim 1, further comprising a notch defined in the one or more lateral walls of the body, the notch extending from a middle portion of the body to a distal end of the body, the recess being defined within the notch. 